1. Field of the Invention
This invention relates to a heald hook lifter.
2. Related Prior Art
A weaving machine includes a plurality of heald hooks each connected between two elastic strings attached to the loom so that the heald hooks, are elastically mounted on the loom. Such heald hooks are disclosed in U.S. Pat. No. 5,095,952. Each of the heald hooks must be moved upwards from time to time during operation of the loom machine. A plastic block is attached to each of the heald hooks. A number of heald hook lifters are mounted on each of a plurality of brackets each connected with a linkage pivotably mounted on the loom. Each of the heald hook lifters includes a blade for abutting against the block attached to a corresponding one of the heald hooks and a link for connecting each of the blades with the bracket. An upper tip of each of the links is secured to the bracket so that each of the links is not pivotable relative to the bracket. Each of the blades is mounted on a corresponding one of the links so that they are not pivotable relative to each other. The heald hooks are movable upwards when the heald hook lifters are movable upwards as the linkage is actuatable. It is desired that each of the blades is movable in a rectilinear path. However, as each of the blades is movable in an arched path, it will be subjected to a bending force as it moves a corresponding one of the heald hooks upwards. The bending forces will produce residue stress in the blades so as to deform the blades, thus biasing the heald hooks from normal positions which results in defects of clothes woven by the loom.